The present invention relates to staplers, and more particularly to a power stapler for bookbinding.
FIG. 1 shows a power stapler according to the prior art which comprises a motor, a transmission gear coupled to the motor, a driven gear wheel meshed with the transmission gear and having an eccentric rod, a forked link, a striking plate pulled by a spring and stopped by the forked link, and an anvil. When the motor is turned on, the driven gear wheel is turned by the transmission gear to move the forked link by the eccentric rod thereof, causing the forked front end of the forked link released from the striking plate, and therefore the spring immediately pulls down the striking plate causing a staple driven through the sheets of paper being placed on the anvil. This structure of Dower stapler is not suitable for fastening a thick stack of paper because the striking plate is not forced downward to strike the staple by a high pressure from the top but simply pulled down by the spring. When the striking plate is pulled to driven a staple through a thick stack of paper, the driven gear wheel or its eccentric rod or the transmission gear may be damaged easily. Another drawback of this structure of power stapler is that the binding position is not adjustable. Still another drawback of this strucutre of power stapler is its complicated structure.
The present invention has been accomplished to provide a power stapler which eliminates the aforesaid drawbacks. According to one aspect of the present invention, the power stapler including a cover shell, a base, a frame, a circuit board assembly, an electromagnetic valve, a magazine and time plate assembly, an anvil, a micro-switch, a presser case assembly, a staple magazine constraint control device, an adjusting rod, and a linkage, wherein the valve block of the electromagnetic valve is controlled by the circuit board to drive the linkage causing the presser case assembly reciprocated to achieve a striking in driving a staple through the sheets of paper to be fastened.
According to another aspect of the present invention, the adjsuting rod can be turned in either direction to move the circuit board assembly in changing the position of the micro-switch so that the binding position is adjusted.
According to still another aspect of the present invention, the staple magazine is automatically pushed out of the magazine seat by a spring for loading staples when the link is rotated.